Explanation:
Let’s just start with rows. I’m going to use a, b, and c for the missing numbers (a in the first row, b in the second, c in the third).
Row 1 — 5 × 4 × a = 1
20 × a = 1 → a = 1/20
Row 2 — b × 1 × 100 = 1
b × 100 = 1 → b = 1/100
Row 3 — 20 × 1/4 × c = 1
5 × c = 1 → c = 1/5
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Check Columns:
5×1/100×20 = 5(20)/100 = 100/100 = 1 ✓
4 × 1 × 1/4 = 1 ✓
1/20×100×1/5 = 100/(20*5) = 100/100 = 1 ✓
Check Diagonals:
5 × 1 × 1/5 = 5/5 = 1 ✓
20 × 1 × 1/20 = 20/20 = 1 ✓